Matthew Fuller, a research assistant at MIT, accidentally invents a time machine while attempting to construct a calibrator to measure the relationships between gravity and light. Unfortunately, it will only travel forward, to the future, in ever-increasing intervals of 12x. On the fifth jump, which sends him forward a few months, he gets arrested for the alleged murder of a drug dealer who actually had a heart attack when he witnessed Matt disappear in his time machine. He is shortly bailed out by someone who can only be from the future, and is left a note urging him to depart in the time machine quickly. He continues forward in time 15 years and upon re-materializing finds that Professor Marsh, his tutor, has taken credit for the time travel invention and subsequently won the Nobel Prize.

Finding no place in this new time, Matt jumps once again into the future and finds himself in a 23rd-century theocracy. Upon arriving, Matt meets a woman named Martha who is assigned to be his servant in the future MIT - the initials now stand for "Massachusetts Institute of Theosophy" and any physics taught there must fit within a neo-Medieval cosmology. This society is dominated by religious fervor. Matt is discovered as being uncircumcised (something that is mandatory in this new and strictly Christian-dominated society - and ironically, Matt, who is an assimilated Jew, did not undergo it). He must flee into the future once again, now accompanied by the loyal Martha.

Matt and Martha arrive several thousand years in the future, just outside of California, in a society where all of humanity is wealthy and satisfied to a point of complete apathy. It is here that they encounter an artificial intelligence that controls Los Angeles, called La. La is curious about her own mortality, and having learned about Matt’s time machine from historical records, wishes to join him on a journey to the end of time (heat death of the universe) to discover if she can die.

At this point, Matt and Martha begin to receive subliminal messages from future versions of Matt, and Martha naively mistakes them to be from Jesus. He/they warn Matt and Martha of La’s willingness to sacrifice their lives in pursuit of her goal, and advises them to stall for time to allow the future Matts to catch up. Matt and Martha, accompanied by La in a spacecraft, begin to travel further and further into the future, discovering radically altered futures and entirely new species of intelligent life, including androgynous evolutions of humanity and a race of intelligent bears.

After a confrontation where they narrowly avoid being killed by La, they meet the people who have been sending them subliminal messages. These beings send Matt and Martha back in time, while allowing La to continue jumping forward in time. The beings can specify either the exact time or the exact location to which Matt and Martha will be sent, but not both (this limitation is similar to the Heisenberg Uncertainty Principle). Concerned about the couple possibly materializing in the middle of the ocean or inside of a mountain, they opt to be specific about location and send them to MIT.

When they arrive, they find that it is the late 19th century, and the main MIT campus in Cambridge has not yet been built. Having no other option, they live in this society, where Matt studies and teaches physics, aided significantly by his advanced knowledge both of physics and historical events. However, he takes care not to change history - for example, he does not anticipate Einstein in "discovering" Relativity Theory, as he could have easily done; rather, he takes care to appear a talented but not outstanding professor. Matt and Martha have several children, and the end of the book reveals that Professor Marsh (Matt's MIT professor in the mid-21st century) is actually Matt's descendant.

Matt, a physics graduate student, establishes himself as an atheist very early on in the novel, through sarcastic references to God and by referring to himself as an “Ex-Reform Jew atheist (95)”, and an “atheist non-practicing Jew”. The strongest representation of this theme takes place in the theocratic society Matt visits on his fourth jaunt through time. It is in this time period that Matt meets Martha, a graduate assistant, at a future MIT where the "T" stands for Theosophy rather than Technology. In this section, a man tells Matt that everything has changed when Jesus returned. We eventually learn that the State has used hologram technology to fool everyone into thinking that Jesus has returned, and uses a mix of technology and religion to maintain its control.

When Matt first encounters Martha she devoutly believes in God, though as she and Matt travel through time she becomes less and less sure of her beliefs, saying, when introduced to sex, “I’m not sure I [believe] anymore, either (233)". Near the end of his time in the theocratic time period, Matt meets a version of Jesus that only appears in holographic form. Later in the novel, a “holy land” is mentioned as being cordoned off by killer satellites called “Avenging Angels". This section characterizes how totalitarian societies may corrupt religious principles to exert control over the masses. Or, it may be read as a criticism of the radical measures a repressive religious society will take to control its citizens and maintain its beliefs.

The character La represents to the extreme the troubling relationship between humans and technology. La is an omniscient machine that controls Los Angeles. La can be in all places at all times, much like God, which is an interesting parallel. Though La is a machine, she can more accurately be described as a hybrid between humanity and technology. La illustrates her human side by wanting to time travel so far into the future to see if she will die; she wants to experience mortality, a very human trait. The fact that the Jesus in the theocratic time period is a hologram represents the way in which technology can exercise its power over humanity by offering salvation in a false savior figure.

The accidental time machine is a metal box with an oak base that was originally created to be a calibrator, but something malfunctioned in another dimension and caused it to time travel when the reset button was hit. It travels roughly in exponents of 11.8 only in a forward direction. It is not capable of being duplicated, and appears to be unique.

February 2, 2059: Matt's first time jump - 39 days. Appears in the middle of the street, still in Boston. He is then arrested for murder and grand theft auto. He is bailed out of jail by a mysterious figure.

May 15, 2060: 465 days later. Appears in the middle of a highway, quickly time travels again to avoid being crushed by a truck.

2074: 15 years later. Matt appears in the middle of a stadium called the "Matthew Fuller Sports Centre". The society is fairly futuristic (with trends like facial scarring), but they do not fully understand the time machine. However, scientific theories are being rewritten because of Matt's time machine.

2252: 177 years later. Matt finds himself by the New Hampshire border in a theocratic society. There had been an event billed as the Second Coming of Jesus, followed by a nuclear civil war between those who believed its veracity and those who doubted it, and with the former group taking power in the eastern part of the US. History has essentially been erased and restarted. The locals refer to the year as 71.

4346: 2094 years later. Matt and Martha arrive in what appears to be a Utopia. The society is based on bartering, is focused on material wealth and there is no poverty or illness. It is highly futuristic/technological and is controlled by an entity called La.

24,000 years later. Martha, La, and Matt land in the Pacific Ocean off the coast of Indonesia, and eventually encounter bioengineered dinosaurs. They continue south to Australia where they are greeted by a hologram, which doesn't allow them to enter the society because they are afraid of disease transmitted by travelers from the past. They travel to America and meet strange bear-like people.

320,000 years. Travel to the moon because there is no life left on Earth. There is only a strange mechanical creature there when they arrive.

3.5 million years later. The couple meet up with six time travelers who send Martha and Matt back to 1898, and La continues forward.

1898. Martha and Matt are back in Boston, from which point they would live out the rest of their lives with no further time traveling.

Haldeman refers to H.G. Wells' classic novel The Time Machine in a brief reference about its protagonist and the Morlock creatures encountered while time traveling (The Accidental Time Machine page 15). The title of Haldeman’s novel itself is both an allusion to and a play on the title of Wells’ novel. The major difference is that Wells’ protagonist purposefully constructs his time machine, while Haldeman’s character simply stumbles upon it.

Similarities:

Both have innocent/ignorant female characters who are saved by the male protagonist

Both have Caucasian, middle-class, heterosexual protagonists who are scientific experts that travel forwards in time by themselves. Furthermore, both seem to belong in the 1890s, which is where Wells’ Time Traveler starts and Matt Fuller ends.

Both have negative consequence of stagnation (indicative that if a society lapses into complete comfort, devolution occurs)

Both have doubtful exterior influences:

Wells' Time Machine: the Time Traveller is doubted by his peers

Accidental Time Machine: Matt is doubted by Professor Marsh

Both encounter seemingly Utopian societies, but quickly realize that they are in fact dystopian

Both are social commentaries on possible avenues humankind could take on the road to devolution

Both critique society, albeit in different forms. In The Time Machine, it is in the form of the dinner guests as vehicles of satire. In The Accidental Time Machine, Haldeman uses the different time periods to critique topics such as religion, nature, and so on.

Both protagonists and the concept of time travel are doubted by those around them in the time periods that they originate from.

Both time machines work, but with some uncertainty and are vulnerable to theft and breakage

Differences:

The time machine is discovered accidentally in Haldeman’s novel, while it is consciously constructed by the time traveler in Wells’ narrative

The Time Machine focuses on class divisions while The Accidental Time Machine focuses on religious and political issues

“He broke a large Ritalin in two and swallowed one half...This would be an all-nighter” (17). Ritalin is a common brand name for the drug methylphenidate. It acts as a central nervous system stimulant, similar in structure to amphetamines and cocaine. Methylphenidate is most commonly prescribed for conditions such as attention deficit disorder (ADD) and narcolepsy. Effects include: increased mental alertness; improved attention and focus; and resistance to fatigue. Abuse of prescription stimulants is higher amongst college students than non-college attending young adults. College students use methylphenidate either as a study aid or to stay awake longer. In being similar (in structure and effect) to “speedy” drugs, such as cocaine and amphetamines, methylphenidate is often referred to, simply, as “speed.”

One of Matt's primary concerns upon discovering the time machine is his legacy as a scientist. He is particularly concerned about keeping his discovery secret, so that he can be a candidate for a Nobel Prize, as a means to scientific notoriety. He later tells his employer, Dr. Marsh, about the time machine, after being arrested for the murder of his drug dealer and friend, Denny Pelosi. Matt's third time jump takes him 15 years into the future, where he discovers that Dr. Marsh has won the Nobel Prize for discovering the phenomenon, which has been dubbed the "Marsh Effect".

The Nobel Prize was established by Alfred Nobel, and is awarded annually for scientific and cultural achievement. It is considered a significant honor to be awarded one. In the novel, the Nobel Prize serves as a symbol of permanence and significance in the novel, and a way of allegorically traveling to the future, and contributing to posterity in a meaningful way. However, the value of this symbol quickly dissolves into meaninglessness the further into the future Matt travels, in parallel with the increasing absurdity and meaninglessness associated with scientific study. The epilogue sees Matt as a professor at MIT, content to remain obscure and unremarkable, perhaps undermining contemporary valuation of scientific legacy.

Haldeman references real-world places to create a visual map for reader to situate the plot. Boston is the main city that is heavily involved in the narrative. When Matt decides to try the time machine himself after a few experiments, he estimates that he will land near the Boston Harbor. Furthermore, Massachusetts Avenue (referred to as "Mass Ave") is frequently travelled by Matt, and is the location where he materializes after he time travels for the first time. Mass Ave joins many municipalities and areas in Massachusetts together such as Cambridge and Arlington, which Matt travels to, and includes real-world landmarks Matt sees such as Harvard Square, Inman Square, Kendall Square and Porter Square.

There are also many references to MIT such as the Green Building which no longer exists in the theocratic future. The Green Building houses the laboratories Matt originally worked in, as well as where he discovers the time machine and eventually steals it. Additionally, the Infinite Corridor and Building 1 are MIT buildings that still exist when Matt goes to his alma mater 177 years later. At the end of the novel, the authors also mention's MIT's original founding location on Boylston Street in Back Bay, Boston.

The Massachusetts Institute of Technology - an institution of which the writer has a considerable personal knowledge, as a longtime teacher of writing at MIT - has an important role in various parts of the book. Matt manages to become a full MIT Professor in three separate periods - in its mid-21st Century incarnation, only slightly removed from the present; in its 23rd Century theocratic role; and lastly (from Matt's point of view), in its late 19th- and early 20th-century origins. The institution is described with considerable affection and much "insider" knowledge of the hidden corners in the MIT campus, of the relations between students and lecturers, and of various wild and rather illicit student practices.

"Even a tiny change here could profoundly affect the future. Don't step on a butterfly." (15)

"But you couldn't come back, like the guy in the Wells novel, and warn everybody about the Morlocks." (15)

"Meanwhile, it wasn't only science that had changed drastically in the past sixteen years. Movies were either dumb static domestic comedies (during which the audience laughed insanely at things that didn't seem to be funny) or brutal bloodbaths from Japan or India." (72)

"Popular books seemed to be written for either slow children or Ph.D's." (73)

"The anomaly of the bioengineered fish was no anomaly, actually; this culture was going to be a mixture of high technology and low. He had to keep his eyes and mind open." (101)

"Believe me the future doesn't get any better on Earth. I've been there. It's a closed book." (243)

"Well you didn't actually 'discover' anything, did you? You just used a component that was faulty in a dimension you can't even sense. Like the family dog accidentally starting the car." (244)

The futures he visits are more commentaries on present day societies, rather than Haldeman’s trying to predict what the future will actually be like. But the science sounds good, and using other worlds to comment on one’s present is a viable, informative, and entertaining literary device with roots that go back to Jonathan Swift, and probably further. And like the best of such literary forerunners, Haldeman doesn’t sacrifice story or character to make his points. The Accidental Time Machine is first and foremost a terrific sf adventure story. Everything else is just icing on an already delicious cake.

Whatever degree Haldeman intends us to take any of this seriously rather pales beside the fact that, SFnally speaking, he's squandering some great opportunities here. We're never in any one of these funhouse futures for long enough to get a real handle on things, to understand why and how the world developed this way. I would have been most intrigued to glean a better understanding of events that led directly from Matt's past to the formation of the 23rd century theocracy. I also think the novel could have been much stronger had Haldeman chosen to leave [Matt] there to make his way as best he could, spreading the forbidden heresy of quantum physics or something. Instead, we get a frenetic final series of chapters, in which millions of years are traversed at the pace of a music video cut together for the ADHD crowd, before [Matt] finally discovers the Secret he's been after all along. It leaves, one might say, something to be desired. So yes, it all starts out as a nice little book about a hapless student who finds himself an unwitting time traveler. And then it just gets silly. And as Col. Chapman might go on to suggest, Haldeman's readers might be much better off with something nice and military.

Haldeman's look at these societies of the centuries to come is intriguing, and even plausible, although I'm honestly sorry he didn't spend longer in some of them. As soon as we got comfortable, he was off again to the next one. I'd have enjoyed seeing Matt stay longer in the future theocracy (where Jesus literally rules) and the future barterocracy (for lack of a better word) as they both held a lot of promise. The deus ex machina which comes into play near the end didn't light my fires either; [...] I don't know what exactly I was expecting; after all, we knew the trip was one-way and if Matt was ever to return to the past (something that was quite broadly suggested to have happened) he had to encounter something capable of reversing the process. I guess it all seemed to end rather abruptly where that point was concerned. This book could have been longer by several hundred pages and I would have been happy.